Brake drum



Patenterl Oct. 4, 1932 UNITED STATES PATENr OFFICE STANLEY M. UDALE, OF DETROIT, MICHIGAN, ASSIGNOR, :BY MESNE ASSIGNMENTS, T0 ERB-JOYCE FOUNDRY COMPANY, OF DETROIT, MIQHIGAN, A CORPORATION OF MIGHIGAN ZBRAKE DRUM Application filed August 29, 1930. Serial No. 478,655.

The object of this invention is to provide a cast iron brake drum having a stamped metal supporting shell and automatic means for ventilating the cast iron brake drum to prevent over-heating.

The ultimate object is to provide a cast iron brake which will remain cylindrcal and will not over heat in service.

Figure 1 shows the brake drum in elevation.

Figure 2 shows a cross section elevation on plane 2-2? offi-.Figure 1.

Fgure, shows a partial elevation on plane 3-3 of Figure1.

In the figures,` A is the brake drum proper;

1 B-B area numberof projections on the outer edge of thebrake drum; C is a flange on the inner edge, D is a sheet steel shell to which the brake drum A is welded. This shell D is provided with openings E-E which serve to act as fan blades drawing air in between the openings B-B over the surface of A and out. The flange D is drilled at F for connection to the wheel or axle.

Method' of vmmufaotum'ng The steel shell D is provided wit-h a taper corresponding to the taper on the edge of the projections B. yShell D is provided with bolt holes F for connections to the wheel or axle.

v The cast iron drum A is forced into the shell vas D until the machined flange C contacts with the shell D. The shell D is then welded to the projections B. The surface A is finally turned cylindrical and concentrically with the holes F--F. By making the shell D taper it is possible to force the cast iron brake drum A to connect both at the projections B--B and at the flange C because the shell D will stretch slightly along its outer open edge thus making a tight fit both at B and C.

Operation The rotation of the wheel causes air to be drawn through the openings between the projections B and out through the fan blades E thus cooling the brake drum. In addition the brake drum is cooled through the flange C which is in contact with D which in its turn is cooled by contact with the wheel and axle. Although the drum A is in contact with the shell D along its flange O, it is not held by D except at the outside edge, hence the fact that D is much cooler than A and C does not cause the braking surface to distort but permits it to remain cylindrical.

What I claim is:

'1. A two piece brake drum comprising a stamped steel shell having a web portion and a cylindrical portion integral therewith, a cast iron brake drum positively held at its outer edge only by the cylindrical portion and the nner edge being in contact with the web portion.

2. A two piece brake drum comprising a stamped steel shell having a web portion and a cylindrcal portion, ventilating vanes in said cylindrical portion, a cast iron brake drum having a plurality of projections on its outer edge, said projections being adapted to engage with the outer edge of the cylindrical portion of said steel shell, the edge of said brake drum being in contact with the flange of the steel shell but not held thereby.

3. A two piece brake drum comprising a stamped steel shell having a web portion and a cylindrical portion integral therewith, a cast iron brake drum positively held at its outer edge only by the cylindrical portion and the inner edge being in Vcontact with the web portion, ventilating vanes in said cylindrical portion for circulating air between the outside of said brake drum and the inside of cylindrical portion of the stamped steel shell.

In testimony whereof I afiix my signature.

STANLEY M. UDALE. 

